(a) Except when a writ of certiorari has been issued by the Supreme Court and the matter is still pending in that court or if as a matter of law the determination of the Supreme Court cannot be subsequently modified, the Workers' Compensation Court of Appeals, for cause, at any time after an award, upon application of either party and not less than five working days after written notice to all interested parties, may set the award aside and grant a new hearing and refer the matter for a determination on its merits to the chief administrative law judge for assignment to a compensation judge, who shall make findings of fact, conclusions of law, and an order of award or disallowance of compensation or other order based on the pleadings and the evidence produced and as required by the provisions of this chapter or rules adopted under it.
(b) As used in this section, the phrase "for cause" is limited to the following:
(1) a mutual mistake of fact;
(2) newly discovered evidence;
(3) fraud; or
(4) a substantial change in medical condition since the time of the award that was clearly not anticipated and could not reasonably have been anticipated at the time of the award.